As I was leaving for daily trip to the Village yesterday I found chickadee huddled in an explosion of fluff on the kitchen window sill. Finches quite often do this and I assume it is to rest and warm.
When I returned the chickadee was on the ground and responded feebly to my touch. I warmed it in my hands and then put it on a soft cloth in a box in the kitchen.
Across the hours it made no further movement.